The accusation is simply false. James Hansen never called for punishment of climate skeptics. This urban myth is likely a deliberate misreading of his actual testimony, designed to turn a carefully worded if provocative indictment of harmful corporate propaganda into a fanatical soundbite. Let’s look at the actual statement:

Special interests have blocked the transition to our renewable energy future. Instead of moving heavily into renewable energies, fossil fuel companies choose to spread doubt about global warming, just as tobacco companies discredited the link between smoking and cancer. Methods are sophisticated, including funding to help shape school textbook discussions of global warming.

CEOs of fossil energy companies know what they are doing and are aware of the long-term consequences of continued business as usual. In my opinion, these CEOs should be tried for high crimes against humanity and nature.

But the conviction of ExxonMobil and Peabody Coal CEOs will be no consolation if we pass on a runaway climate to our children. Humanity would be impoverished by ravages of continually shifting shorelines and intensification of regional climate extremes. Loss of countless species would leave a more desolate planet.

Hansen is clearly not talking about climate change skeptics, not even blatantly dishonest ones. He is talking about fossil-fuel company CEOs who knowingly and deliberately promote false information and doubt about the reality and potential consequences of climate disruption from fossil-fuel emissions. (It is also worth noting that he thinks they should be tried, not summarily convicted.) Given what the world has at stake, is this really such an extreme sentiment?

Imagine you are in a movie theater. Someone smells smoke and yells “Fire!”, but the theater owner, despite knowing the fire is real, doesn’t want to refund the price of admission. So rather than evacuating, he tells everyone to stay and enjoy the end of the film — there is nothing to worry about. If the fire spreads and people die as a result, wouldn’t the theater owner be responsible in some way? Readers may have their own opinions about the morality of that question, but the laws are pretty clear that yes this is a criminal case. It would be a criminal case even if the owner thought he could put the fire out by himself, and indeed tried his best.

Measurement of health effects from climate change can only be very approximate. Nevertheless, a WHO quantitative assessment, taking into account only a subset of the possible health impacts, concluded that the effects of the climate change that has occurred since the mid-1970s may have caused over 150,000 deaths in 2000. It also concluded that these impacts are likely to increase in the future.

There is also ample evidence that the people orchestrating the propaganda campaigns know very well that they are not making a factual case at all (sometimes known as lying). There are even historical precedents for holding corporations liable for intentional disinformation campaigns that lead to death and disease, like the litigation against the tobacco industry. (It is interesting to note that there are a remarkable number of names common to global warming denial and tobacco-cancer denial, including but not limited to Fred S. Singer, Fred Seitz, Steve Milloy, and Myron Ebell.)

So while reasonable people may disagree that trying CEOs who are funding tragically harmful propaganda is a good thing to suggest, or a good thing to do, given the facts outlined above it is hardly similar to the Vatican trying Galileo for heresy! It also has no relevance whatsoever to the potential publication of skeptical research contradicting the prevailing scientific opinion.

Whatever you may think of what he actually did say, James Hansen clearly did not call for the punishment of anyone based on failure to accept the reality of anthropogenic global warming.